BOOK REVIEW / BIOGRAPHY : A Dark Life With a Familiar Ring : GRAHAM GREENE: The Enemy Within <i> by Michael Shelden</i> ; Random House $25, 442 pages

In the 1950s, when a friend asked Graham Greene why he converted to Catholicism in his 20s, the writer replied, “I had to find a religion . . . to measure my evil against.” Michael Shelden, author of “Graham Greene: The Enemy Within,” says the great novelist may have been joking, but many eyebrows will rise at Shelden’s gloss, which occurs a quarter of the way into this biography.

Greene’s statement seems perfectly in keeping with what has been, from the very first page, an exceptionally negative portrait, and one wonders--not for the first time, nor the last--why Shelden doesn’t want to take an apparently serious comment seriously. Could he really dislike his subject so much that he hopes to deny Greene even the self-knowledge this striking confession intimates?

Shelden, an English professor at Indiana State, in 1991 published a good and admiring biography of George Orwell that emphasized the writer’s virtue, courage, sincerity and moral force. Shelden, in Greene, seems to have found Orwell’s virtual shadow; this Greene is an appalling, hateful man--anti-Semitic, anti-Christian, anti-American, possibly pederastic, certainly priapic, mean-spirited and, above all, “disloyal to the core.”

It’s easy to speculate--and Shelden does a lot of speculating in this biography, so he’s made the practice fair game--that Greene’s sins seem particularly offensive to an Orwell fan, and help explain Shelden’s extraordinarily judgmental tone. Given the facts, perhaps it’s legitimate for Shelden to describe Greene as “the Harry Lime of the literary racket,” referring to the evil genius of “The Third Man” . . . but not at all to suggest, with laughably negligible evidence, that the novelist may have had something to do with a macabre unsolved murder.

Biographies, once upon a time, consisted of relatively straightforward life stories, intermittently enlarged with personal and thematic analyses. That’s what we got in Shelden’s Orwell biography; it’s another story here, though, for much of the time you can’t tell where Greene the lascivious, manipulative writer leaves off and Shelden the righteous, outraged biographer begins.

This biography, in short, wouldn’t appear to inspire trust--except that the numerous books on Greene published since his death in 1991 concede most of the faults highlighted by Shelden. Even Greene’s authorized biographer, Norman Sherry, acknowledged his subject’s heavy drinking, drug use, and weakness for prostitutes and general duplicity. Yet Sherry still managed to produce--according to Thomas Disch, who in March reviewed for The Times the second of Sherry’s three projected volumes--a likeness of “skilled and persuasive flattery” comparable to portraits commissioned by renaissance popes.

Shelden makes reference to Sherry’s biography in an author’s note, and it seems clear that Shelden’s vitriol--Orwell aside--is linked to the kid-glove treatment Greene routinely enjoyed at the hands of most every commentator. Shelden’s ire also seems a natural result of his biographical approach; attempting to understand Greene primarily through his writing, he uncovers--should we be surprised?--that the hate, amorality and duplicity found there is likewise found in Greene’s character.

It’s amusing as well as telling that the famously Catholic Greene, after publishing such classic depictions of evil and vice as “Brighton Rock” and “The Power and the Glory,” should become managing director at Eyre & Spottiswoode, a publishing house kept afloat by its best-selling edition of the Bible.

Soon after making that point, Shelden quotes Greene’s superior at Eyre & Spottiswoode as describing the novelist’s best books--the two just mentioned, plus “The Heart of the Matter”--as saturated with “emotion recollected in hostility.” It’s an apt description, and both more memorable, and more temperate, than any put forward by Shelden himself. Shelden recognizes that one of Greene’s greatest talents was the ability to compel readers to sympathize with malevolent, unscrupulous, even loathsome characters, but that’s not a talent he shares.